There is great variation in the lithology and lamination thickness of composite roof in coal-measure strata;thus,the roof is prone to delamination and falling,and it is difficult to control the surrounding rock when d...There is great variation in the lithology and lamination thickness of composite roof in coal-measure strata;thus,the roof is prone to delamination and falling,and it is difficult to control the surrounding rock when developing roadway in such rock strata.In deep mining,the stress environment of surrounding rock is complex,and the mechanical response of the rock mass is different from that of the shallow rock mass.For composite-roof roadway excavated in deep rock mass,the key to safe and efficient production of the mine is ensuring the stability of the roadway.The present paper obtains typical failure characteristics and deformation and failure mechanisms of composite-roof roadway with a buried depth of 650 m at Zhaozhuang Coal Mine(Shanxi Province,China).On the basis of determining a reasonable cross-section shape of the roadway and according to the failure characteristics of the composite roof in different regions,the roof is divided into an unstable layer,metastable layer,and stable layer.The controlled unstable layer and metastable layer are regarded as a small structure while the stable layer is regarded as a large structure.A superimposed coupling support technology of large and small structures with a multi-level prestressed bearing arch formed by strong rebar bolts and highly prestressed cable bolts is put forward.The support technology provides good application results in the field.The study thus provides theoretical support and technical guidance for ground control under similar geological conditions.展开更多
This paper analyzed the strata behaviors of solid-coal roadway, gob-side entry driving and deformation law of surrounding rock in depth under high stress and thick composite roof based on the dynamic pressure roadway ...This paper analyzed the strata behaviors of solid-coal roadway, gob-side entry driving and deformation law of surrounding rock in depth under high stress and thick composite roof based on the dynamic pressure roadway as engineering background in Fengcheng mining area, Jiangxi province. The results, both field measurement and numerical simulation show that gob-side entry driving results the deformation of coal roadway main wall, however, entity-coal roadway driving results deformation of main roof and floor. The maintenance state of gob-side entry driving is better than entity-coal roadway, this situation is relevant to thick composite roof layered and easy collapse characteristics. At the same time, this paper put fox＇ward and proved proper dynamic pressure roadway supporting scheme under the surrounding rock condition and stress environment.展开更多
Roof greening is crucial for improving urban eco-environment, showing benefits, ecological y or social y, but it is so hard for investors in terms of capitals or promotion. The research introduced sponge-type composit...Roof greening is crucial for improving urban eco-environment, showing benefits, ecological y or social y, but it is so hard for investors in terms of capitals or promotion. The research introduced sponge-type composite vegetation carpet techniques and constructionprocess, making a breakthrough in greening form and having formulated a new one.展开更多
基金This study was supported by the National Natural Science Foundation of China(No.51804310No.52074301)Fundamental Research Funds for the Central Universities(No.2020XJNY05).
文摘There is great variation in the lithology and lamination thickness of composite roof in coal-measure strata;thus,the roof is prone to delamination and falling,and it is difficult to control the surrounding rock when developing roadway in such rock strata.In deep mining,the stress environment of surrounding rock is complex,and the mechanical response of the rock mass is different from that of the shallow rock mass.For composite-roof roadway excavated in deep rock mass,the key to safe and efficient production of the mine is ensuring the stability of the roadway.The present paper obtains typical failure characteristics and deformation and failure mechanisms of composite-roof roadway with a buried depth of 650 m at Zhaozhuang Coal Mine(Shanxi Province,China).On the basis of determining a reasonable cross-section shape of the roadway and according to the failure characteristics of the composite roof in different regions,the roof is divided into an unstable layer,metastable layer,and stable layer.The controlled unstable layer and metastable layer are regarded as a small structure while the stable layer is regarded as a large structure.A superimposed coupling support technology of large and small structures with a multi-level prestressed bearing arch formed by strong rebar bolts and highly prestressed cable bolts is put forward.The support technology provides good application results in the field.The study thus provides theoretical support and technical guidance for ground control under similar geological conditions.
基金Supported by the National Natural Science Foundation of China （51074071） the Scientific Research Fund of Hunan Provincial Education Department （12cy013）
文摘This paper analyzed the strata behaviors of solid-coal roadway, gob-side entry driving and deformation law of surrounding rock in depth under high stress and thick composite roof based on the dynamic pressure roadway as engineering background in Fengcheng mining area, Jiangxi province. The results, both field measurement and numerical simulation show that gob-side entry driving results the deformation of coal roadway main wall, however, entity-coal roadway driving results deformation of main roof and floor. The maintenance state of gob-side entry driving is better than entity-coal roadway, this situation is relevant to thick composite roof layered and easy collapse characteristics. At the same time, this paper put fox＇ward and proved proper dynamic pressure roadway supporting scheme under the surrounding rock condition and stress environment.
基金Supported by Guangdong Province Soft Science Research Program(2014B090903015)Guangdong Province Science&Technology Cooperation Program([2015]162)~~
文摘Roof greening is crucial for improving urban eco-environment, showing benefits, ecological y or social y, but it is so hard for investors in terms of capitals or promotion. The research introduced sponge-type composite vegetation carpet techniques and constructionprocess, making a breakthrough in greening form and having formulated a new one.
